ZF 4699.825.180 GP25 | OEM Genuine Part

Overview

The ZF 4699.825.180 GP25 is a critical OEM genuine gear set component engineered for heavy-duty construction machinery transmissions. Positioned within the planetary gear train of ZF’s modular transmission systems, this part directly facilitates torque distribution and speed reduction during high-load operations. The SKU 4699.825.180 serves as the primary power transfer interface between the input shaft and the output assembly, ensuring synchronized gear engagement under extreme stress. Designed to withstand continuous shock loads in excavators, wheel loaders, and graders, this GP25 unit is precision-machined from case-hardened alloy steel to maintain dimensional stability over extended service intervals.

Symptoms of Failure

• Intermittent gear slipping under load – When the GP25 wears, operators often report sudden loss of drive power during uphill climbs or when digging, particularly in WG180 transmissions.
• Metallic grinding noise during shifting – A distinct whining or grinding sound from the transmission housing indicates tooth surface fatigue on the 4699.825.180 gear set.
• Hydraulic oil contamination with metal particles – Worn GP25 teeth shed fine metallic debris into the transmission fluid, visible during routine oil changes as glitter-like particles.
• Delayed engagement in forward/reverse – Excessive backlash from a degraded GP25 causes a noticeable lag when shifting between drive modes, often misdiagnosed as a valve body issue.

Technical Specifications

Compatibility

This GP25 gear set is specifically designed for ZF WG180 and WG200 series transmissions commonly found in construction machinery. It also fits select WG150 and WG250 variants used in telescopic handlers and compact loaders. Always verify your transmission model suffix (e.g., WG180-3 or WG200-5) before ordering, as minor spline variations exist across production years. The 4699.825.180 is not compatible with WG310 or WG500 series units.

During installation, we recommend pairing this GP25 with the 4699025080 GP25 companion gear for matched wear patterns. The 4699101158 HOUSING must be inspected for cracks, while the 4699102095 INPUT shaft and 4699103075 OUTPUT flange should be replaced simultaneously to prevent premature failure. Always use new 0634801038 SEALING RING and 0636100132 TORX SCREW fasteners during reassembly.

Related Components